Neutrophil Gelatinase-Associated Lipocalin
Neutrophil Gelatinase-Associated Lipocalin (NGAL), also known as Lipocalin-2, forms a disulfide bond-linked heterodimer with MMP-9. It mediates an innate immune response to bacterial infection by sequestrating iron. Lipocalins interact with many different molecules such as cell surface receptors and proteases, and play a role in a variety of processes such as cancer and allergy. Iron-trafficking protein involved in multiple processes such as apoptosis, innate immunity, and renal development. Involved in apoptosis due to interleukin-3 (IL-3) deprivation: iron-loaded form increases intracellular iron concentration without promoting apoptosis, while iron-free form decreases intracellular iron levels, inducing expression of the proapoptotic protein BCL2L11/BIM, resulting in apoptosis. Involved in innate immunity, possibly by sequestrating iron, leading to limit bacterial growth. NGAL levels rise in urine and blood within 2 hours of renal insult making NGAL a biomarker for acute renal injury.
Swiss-Prot Accession Number: P80188